If you notice that the air supply to the car decreased dramatically, it is preferable to replace the salon filter before this is provided by the BMW 3 E46 BMW (every 2 years or every 20,000 km). The filter is located in the catchment below the hood cover. To replace a filter element in it, you must:
1. Open the hood and turn the clamps -1 to 900.
2. Remove the cover of the air filter.
3. To fill an old filter element and place a new one.
4. Insert the cover from the front, pivot the clamps back and close the bonnet.